For UV purification, the SteriPEN Adventurer Opti is lighter, smaller, and more reliable than the old SteriPen Journey LCD. SteriPEN seems to have overcome a few of the finicky reliability issues with this model, and have developed a more compact and easy to use unit, though the green or red light indicating if it worked can be hard to see. It also has the fun feature of doubling as a flashlight. It is not as low maintenance as a simple and long-lasting filter unit like the Sawyer Squeeze since it still requires battery changing and monitoring.
As with all SteriPENS, with the Adventurer you are limited to what size and type of container you can use to purify your water in, and it does not strain out particulate, requiring the user to be more diligent in selection of water sources. It does, however, have the added benefit of treating viruses, making it a particularly desirable choice for international travel. Weighing 4.61 ounces, the Adventurer is an excellent option for a weight conscious hiker who wants a chemical-free purification method.